| Author |
Message |
bill chisholm (Billybandman) (169.204.196.20)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 1:30 pm: | |
In the continuing effort to make my GMC 4108 steer like a 2005 Dodge Viper I literally replaced every possible part known to bus science, which has made a huge difference and and now I would like to align the front end. The last time I had it aligned commercially the guy wouldn't toe it in so I wouldn't pay him. I understand that in order to make this thing abosolutely perfect it should be toed in about 1/8th inch. Where is that 1/8 measured; is that the difference of the distance between the rear of the front tires and the front of the front tires, or is it mearsured from the break drums, or ???? |
TWO DOGS (63.185.81.198)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 2:28 pm: | |
tires |
BrianMCI96A3 (198.81.26.45)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 2:52 pm: | |
Bill, how we did it in the past was to jack up the front axle until the wheels were just able to spin free, put a jack stand in front of each tire in the middle of the tire.
With a piece of chalk resting on the jack stand, spin the each tire and bring the chalk in contact with the tires so that it makes a mark all the way around the tire.
Measure the distance between the chalk lines at the middle height off the ground in front and back of the tire.
Brian |
Jimmci9 (209.240.205.68)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 3:27 pm: | |
if you dont like the chalk idea, while you have the tire up off the ground, spin it... while its spinning, use areosol (spray) paint, to paint a stripe around the tread of the tire.. then hold a screwdriver against the bumper where it rubs in the paintstripe.. spin tire again.. the scribe mark will be narower than chalk... set the tire back on the ground.. measure between marks, comparing front and back... make sure all the load is on the axle that will normally be there...set to 1/8 to 1/16th difference... more for bias tires... less for radial...then lock down the clamps on the tie-rods... |
Ron Leiferman (Ron_In_Sd) (12.111.217.5)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 4:46 pm: | |
The way I messure toe is with a $35 from a racing supply warehouse.
The unit has two arms that slide over a straight pipe and lock down with set screws. On each arm is two pins one pointing forward and one pointing backwards. You put a peice of tape on the front side of each tire and then poke the pins into the tape. Pull the bar back out from under the bus. You roll the bus backward until the tape in on the backside of the tire. (You always roll backwards so your tape does not touch the ground and get marks on it.) You slide the bar back under the bus on the backside of the tire. You then place one pin back in the orginal hole and they you poke another hole in the peice of tape on the other tire. The differance between the two pin holes is the toe. You don't have to jack up the bus at all.
In order to get a good messurement always move the bus back and forward in a straight line a couple times before starting. This will help even out the "load" on the tires from turning and setting for a long time. Make sure the bus has normal air pressure when doing the test and the tires are at their need/rated air pressure. Make sure the bus is loaded the way it will be for most of your trips. Fuel and water levels should be close to normal.
It is really easy when you get the hang of it. |
bill chisholm (Billybandman) (169.204.196.20)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 5:26 pm: | |
Thanks for the ideas. Some even sound like they would work |
Sam Sperbeck (204.248.119.254)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 5:53 pm: | |
Hi Billy,
As you may already know, there is more to alignment than toe-in. Is the 1/8" figure you mention from the manual or what someone told you it should be? Our 4106 was set at "0" by the alignment shop 15 years ago and steers just fine so the alignment shop you took your bus to may have been right in refusing to toe yours in.
Thanks, Sam Sperbeck
La Crescent, MN |
Tom Caffrey (Pvcces) (65.74.65.65)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 9:18 pm: | |
Billy, we have the same spec in the manual for our 4106. I wondered about where the measurement was to be taken until I saw that the method measured the difference between the front and the rear of the tires.
When Les Schwab did the toe on ours, the mechanic told me that if the tires were conventionals, 1/8" would be fine. Since we have radials, however, he said that the best practice was to get them as close to zero as he could, on the toe-in side if they were slightly off of zero.
He said that 1/8" was too much toe-in for these radials.
We had that work done around 15,000 miles ago. I can't see any sign of wear due to toe settings and the coach steers fine, as far as I can tell.
For what it's worth.
Tom Caffrey PD4106-2576
Suncatcher |
Frank Allen (152.163.252.199)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 11, 2004 - 11:12 pm: | |
I set mine at 1/8 and put 5 degrees of caster in it, works fine for us
Frank allen
4106 |
RayC (142.165.92.240)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 12, 2004 - 5:37 pm: | |
I think you have had some good info on setting toe but below is an article from an older alignment manual on toe.(It will not apply to FWD vehicles which often run toe out because of different dynamics)
GREATEST CAUSE OF TIRE WEAR IS
Excessive toe—in or excessive toe—out.
Toe—in or toe—out is the difference in distance between the extreme front and extreme rear of the tires at spindle height.
The theory that the amount of toe—in is governed by the amount of positive caster is not true. Tests show that camber wear is not associated with the wear caused by improper toe—in and that the two angles are not dependent upon each other in any way.
Maximum tire mileage is obtained when the toe is running zero. To obtain a running toe of zero for average driving it is usually necessary to adjust the front wheels with a small amount of toe—in. This is especially true when the steering mechanism is loose because looseness may change the toe—in to toe—out, and toe—out can produce wander. Toe— in will not cause any more tire wear than an equal amount of toe—out, but to avoid wander it is more desirable to have a slight amount of toe—in.
When a vehicle is in forward motion a force is set-up in the steering linkage which compresses the tie-rod and the tie-rod ends to produce a spreading of the wheels at the front, therefore the recommended toe- in setting is desirable. |
bill chisholm (Billybandman) (169.204.196.20)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 12, 2004 - 5:55 pm: | |
Ray C
I believe you are "ight on"in that a little toe in is necessary to compenste for the "force". I would also error on the tire wear side to have less wander. These tires rot off before I can put the maximun mileage on 'em. I really don't care about a little extra wear. I think I am going to set the toe in at 1/8" and see how it goes. Its easy to change it to less if smoke starts coming from under the tires..back to neutral. This board makes me laugh...ask how to do something..and you get theory about why you should or shouldn't. |
Jerry (205.188.116.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 13, 2004 - 9:17 am: | |
I wish this post was here just a few days earlier -- figured there was probably a way to do-it-oneself -- like I do most everything else on my bus. I needed new tires and thought while I was there and especially since I had not done it once I changed over to power steering (did a quick tape measure thing to get it close), thought I'd get it done by the "professionals." Granted they had fancier equipment but mostly really all I did was lighten my wallet about $250 for what I could have done at home -- live and learn. I'm printing out the above posts to put in that section of my '06 manual. |
Adame (129.82.52.179)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, May 15, 2004 - 11:00 am: | |
The reason that toe in is used is because as you drive down the road, the rolling resistance between the tires and the road causes a torque at the king pins or ball joints, whichever applies. This force makes the system want to toe out. The toe in setting is a guesstimate of how much slack is in the pivot points that keep your tires pointed forward. A system with all new parts would require less toe in than a worn system.Simply stated, the toe in setting compensates for this slack
Bob |
DaveD (64.235.199.184)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, May 16, 2004 - 7:47 am: | |
The $250.00 sounds a little steep. How did they do on centering the steering wheel?
Dave Dulmage
(MC-8) |
Stephen Fessenden (Sffess) (65.130.8.165)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 20, 2004 - 1:23 am: | |
I had someone mis set toe in on a car to slight toe out and it darted to one side or the other. Not wandered. Darted suddenly because there was no counterforce from the opposite tire to center the steering. |